function temp = deal(f, z0, n, m);
    syms np dif difz z

    if z0 > m
        temp = 0;
    elseif 0 < z0 && z0 < m
        dif = diff(f, z, n - 1);
        difz = subs(dif, z, z0);
        np = prod(1, n - 1);
        temp = 2 * pi * i * difz / np;
    end

end
